<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>常见网页布局3</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        li {
            list-style: none;
            /* 去除小圆点 */
        }
        .top {
            height: 50px;
            background-color: gray;
        }
        .banner {
            width: 980px;
            height: 150px;
            background-color: gray;
            margin: 10px auto;
        }
        .box {
            width: 980px;
            margin: 0 auto;
            height: 300px;
            background-color: aliceblue;
        }
        .box li {
            width: 237px;
            height: 300px;
            background-color: gray;
            float: left;
            margin-right: 10px;
        }
        .box .last {
            margin-right: 0;
        }
        /* 只要是通栏的盒子（和浏览器一样宽）不用设置宽度 */
        .footer {
            height: 200px;
            background-color: grey;
            margin-top: 10px;
        }
        /* 盒子与盒子之间距离用margin调节 */
    </style>
</head>
<body>
    <!-- .top+.banner+.box+.footer快速创建以下四个盒子 -->
    <div class="top">top</div>
    <div class="banner">banner</div>
    <div class="box">
        <ul>
            <li>1</li>
            <li>2</li>
            <li>3</li>
            <li class="last">4</li>
        </ul>
    </div>
    <div class="footer">footer</div>
    <img src="img/常见网页布局3.1.png" alt=""><br>
    <img src="img/常见网页布局3.2.png" alt="">
</body>
</html>